Devonian to Permian plate tectonic cycle of the Paleo-Tethys Orogen in southwest China (I): Geochemistry of ophiolites, arc/back-arc assemblages and within-plate igneous rocks
Devonian to Permian plate tectonic cycle of the Paleo-Tethys Orogen in southwest China (I): Geochemistry of ophiolites, arc/back-arc assemblages and within-plate igneous rocks
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中国西南古特提斯造山带泥盆纪-二叠纪板块构造旋回（一）：蛇绿岩、弧/弧后组合及板内火成岩地球化学
DOI：
10.1016/j.lithos.2009.04.004
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发表时间：
2009-12
期刊：
影响因子：
3.5
通讯作者：
Qi Zhang
中科院分区：
文献类型：
--
作者：
Alfred Kröner;Xiaomeng Sun;Wei Zhang;Dunyi Liu;Yizhao Wang;Ping Jian;Qi Zhang
中国西南古特提斯造山带是以哀牢山、金沙江和昌宁-孟连蛇绿岩带为界的大陆造山带（锡布马苏、思茅和扬子）的拼合体。本研究集中在蛇绿岩，弧/弧后组合，板内火成岩发生在这个复杂的造山带。根据玄武岩的地球化学特征，将古特提斯蛇绿岩划分为MORB型和SSZ型。哀牢山蛇绿岩（NMORB型，约387-374 Ma）与扬子西缘裂谷的非火山岩段有关。金沙江蛇绿岩（EMORB型; 346-341 Ma），具有蛇绿岩结构，但一些样品具有地壳混染的标志，与裂谷扬子西缘的火山岩段。这些MORB型蛇绿岩被解释为形成于大陆-海洋过渡带。昌宁-孟连蛇绿岩标志着古特提斯缝合带的主要部分，即冈瓦纳大陆的西布马苏蛇绿岩和长江大陆的思茅蛇绿岩的分界线，传统上认为其起源于大洋中脊（莫尔）。然而，玄武岩的新微量元素数据表明，这条蛇绿岩（约。270-264 Ma）形成于超俯冲带（SSZ）。弧和弧后组合由吉查（约。1777年（昭和27年），改隶。288-284 Ma）环带镁铁质-超镁铁质杂岩和崖县桥弧火山岩（约. 268-264 Ma）。地球化学数据表明，Gicha复杂起源于弧后裂谷。半坡杂岩形成了一个含低钛辉长岩和英云闪长岩的深成弧，与火山弧花岗岩（VAG）有密切关系。板内火成岩被认为是捕虏体（角闪岩;约。443-401 Ma）和大龙开小型分异镁铁质-超镁铁质侵入体（ca. 247-244 Ma）侵入了雅仙桥弧。角闪岩捕虏体的成分与低钛大陆溢流玄武岩（CFB）相似。来自小型镁铁质-超镁铁质侵入体的岩石具有叠加俯冲和板内地球化学特征。这些蛇绿岩、弧/弧后组合和板内火成岩是古特提斯板块构造旋回演化的岩浆记录。
The Paleo-Tethys Orogen in southwest China is an amalgamation of continental terranes (Sibumasu, Simao and Yangtze), which are bounded by ophiolite belts (Ailaoshan, Jinshajiang and Changning–Menglian) that represent former ocean basins. This study concentrates on ophiolites, arc/back-arc assemblages, and within-plate igneous rocks that occur in this complex orogen. Mainly based on geochemical fingerprinting of basalts, the Paleo-Tethys ophiolites are here classified as MORB and SSZ types. The Ailaoshan ophiolite (NMORB-type; ca. 387–374 Ma) is associated with a non-volcanic segment of the rifted western Yangtze margin. The Jinshajiang ophiolite (EMORB-type; 346–341 Ma), which has ophiolite structure but some samples bear crustal contamination signatures, is associated with a volcanic segment of the rifted Yangtze western margin. These MORB-type ophiolites are interpreted to have formed in the continent-ocean transition zones. The Changning–Menglian ophiolite, which marks the main Paleo-Tethys suture, that is, the boundary between the Gondwana-derived Sibumasu terrane and the Yangtze-derived Simao terrane, has traditionally been thought to have a mid-ocean ridge (MOR) origin. New trace element data of basalts, however, indicate that this ophiolite (ca. 270–264 Ma) was formed at a supra-subduction zone (SSZ). Arc and back-arc assemblages are represented by the Gicha (ca. 311–277 Ma) and Banpo (ca. 288–284 Ma) zoned mafic-ultramafic complexes and the Yaxianqiao arc volcanic rocks (ca. 268–264 Ma). Geochemical data suggest that the Gicha complex originated in a back-arc rift. The Banpo complex makes a plutonic arc that contains low-Ti gabbro and tonalite with volcanic arc granite (VAG) affinity. Within-plate igneous rocks are recognized as xenoliths (amphibolites; ca. 443–401 Ma) in the Jinshajinag ophiolite mélange and the Dalongkai small differentiated mafic-ultramafic intrusion (ca. 247–244 Ma) that intruded the Yaxianqiao Arc. The amphibolite xenoliths are similar to low-Ti continental flood basalts (CFB) in composition. Rocks from the small mafic-ultramafic intrusion have superimposed subduction and within-plate geochemical signatures. These ophiolites, arc/back-arc assemblages and within-plate igneous rocks, are summarized as the magmatic records for the Plaeo-Tethys evolution in the context of a plate tectonic cycle.
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影响因子：
3.5
作者：
A. Montanini;R. Tribuzio;L. Vernia
通讯作者：
A. Montanini;R. Tribuzio;L. Vernia
DOI：
10.1098/rsta.1984.0014
发表时间：
1984-04
期刊：
Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
影响因子：
--
作者：
R. Thorpe;Peter Francis;L. O'callaghan
通讯作者：
R. Thorpe;Peter Francis;L. O'callaghan
影响因子：
2.9
作者：
COLEMAN, RG;MCGUIRE, AV
通讯作者：
MCGUIRE, AV
影响因子：
3.9
作者：
O. Féménias;N. Coussaert;B. Bingen;M. Whitehouse;J. C. Mercier;D. Demaiffe
通讯作者：
O. Féménias;N. Coussaert;B. Bingen;M. Whitehouse;J. C. Mercier;D. Demaiffe
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift